This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R6020, R6080, R6120, R6220, R6260, R6700v2, R6800, R6900v2, R7450, JNR3210, WNR2020, Nighthawk AC2100, and Nighthawk AC2400 firmware version 1.2.0.62_1.0.1 routers. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed. The specific flaw exists within the mini_httpd service, which listens on TCP port 80 by default. When parsing the funjsq_access_token parameter, the process does not properly validate a user-supplied string before using it to execute a system call. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-11653.

References

• https://nvd.nist.gov/vuln/detail/CVE-2020-27867
• https://kb.netgear.com/000062641/Security-Advisory-for-Password-Recovery-Vulnerabilities-on-Some-Routers
• https://www.zerodayinitiative.com/advisories/ZDI-20-1423/